Recently, in an LSI formed on a silicon substrate, a performance of the LSI is enhanced by miniaturization of an element. When a MISFET (Metal Insulator Semiconductor Field Effect Transistor) is used, it becomes difficult to reduce a power supply voltage and to suppress a leakage current as miniaturization is progressed, and therefore it is difficult to realize an LSI whose power consumption is further reduced.
A three-terminal tunnel transistor controls a tunnel current of a p-n junction made between a drain and a source by a gate voltage. Since Id-Vg characteristics of the tunnel transistor change steeply as compared with a MISFET, the tunnel transistor is expected to reduce a power supply voltage and a power consumption.
In the tunnel transistor, a source and a drain have a different conductivity type, and in, for example, an N-type tunnel transistor, a source is a P-type and a drain is an N-type. Accordingly, the tunnel transistor has such characteristics that when a voltage between a gate and a source is zero, even if a positive voltage is applied to a drain on the basis of a source, a current can be cut off, whereas when the positive voltage is applied to the source on the basis of the drain, the current cannot be cut off.
Due to the characteristics described above, in a pass gate composed of one MISFET for controlling a bidirectional current, when the MISFET is replaced with a tunnel transistor as it is, the bidirectional current cannot be cut off.